Khatib Milad, Kahil Maher, Soliman Mohamed Reda
ISSEA-Cnam, Zkak Blat Maurice Barres, Beirut, Lebanon.
Beirut Arab University, Faculty of Engineering, Civil and Environmental Engineering Department, Lebanon.
Heliyon. 2023 Jul 17;9(7):e18169. doi: 10.1016/j.heliyon.2023.e18169. eCollection 2023 Jul.
Qaraoun Lake, the largest artificial lake in Lebanon, suffered severe environmental issues due to discharging untreated domestic and industrial wastewater into it, throwing garbage, which transformed this lake into waste storage instead of using the water for agricultural purposes and making the surrounding places attractive for tourists as was before. Moreover, the violations on Litany River, Lebanon's main artery, also affected Qaraoun Lake. Therefore, this main reservoir suffers from annual blooms of potentially toxic cyanobacteria. Recently, tons of fish are washed up at the surface of the water, agricultural areas are irrigated with polluted water and the Qaraoun Lake is no longer an attractive touristic place. Besides, the climate change represented in lower precipitation and higher evaporation rates in the past few years in addition to the increase in the water demand due to the growth in the local population and the refugees from nearby countries have affected the vulnerability of the water sector in Lebanon. All these issues have resulted in the deterioration of the water quality, generating environmental issues, and seriously affecting the ecosystem. The purpose of this research is to investigate possible remediation strategies, which could help in the restoration of the Qaraoun reservoir. For this purpose, the Litani River water quality and hydrological data are collected from the Litani River Authority (LRA). Moreover, a hydrodynamic water quality model has been developed using Mike21 in order to restore the lake's aquatic life by eliminating the Litani River nutrients through constructed wetland concept, which reasonably simulated the water quality parameters of Qaraoun Lake. Consequently, the wetland could remarkably reduce the Litani River pollutants by 85%, 43.7%, 57%, and 56% for BOD, Phosphorous, Nitrate, and Ammonia, respectively. The resulted treated water, after passing the wetland, successfully improved the lake water quality and may lead to re-originate its ecosystem.
卡拉oun湖是黎巴嫩最大的人工湖，由于向湖中排放未经处理的生活和工业废水、倾倒垃圾，遭受了严重的环境问题，这使得该湖变成了垃圾储存地，而不是用于农业灌溉，也无法像以前那样让周边地区吸引游客。此外，对黎巴嫩主要动脉利塔尼河的破坏也影响了卡拉oun湖。因此，这个主要水库每年都遭受潜在有毒蓝藻的大量繁殖。最近，大量鱼类被冲到水面，农业区用污水灌溉，卡拉oun湖不再是一个有吸引力的旅游地。此外，过去几年降水减少、蒸发率升高所代表的气候变化，加上当地人口增长和来自周边国家的难民导致的用水需求增加，都影响了黎巴嫩水部门的脆弱性。所有这些问题都导致了水质恶化，产生了环境问题，并严重影响了生态系统。本研究的目的是调查可能的修复策略，以帮助恢复卡拉oun水库。为此，从利塔尼河管理局（LRA）收集了利塔尼河的水质和水文数据。此外，还使用Mike21开发了一个水动力水质模型，通过构建湿地概念去除利塔尼河的营养物质，以恢复湖泊的水生生物，该模型合理地模拟了卡拉oun湖的水质参数。因此，湿地可以分别将利塔尼河的生化需氧量、磷、硝酸盐和氨的污染物显著减少85%、43.7%、57%和56%。经过湿地处理后的水成功改善了湖水水质，并可能导致其生态系统重新恢复。
